Computer network card
Let’s start our topic with the fact that network cards are different and may differ, both in the range of tasks to be solved and in the form factor (appearance). A network card is also often referred to as an Ethernet (Ethernet) controller, network adapter or NIC (Network Interface Card) adapter.
First of all, let’s divide network cards into two large groups:
External network cards
Built-in or integrated (onboard)
Let’s start with the external ones. From the name itself, it follows that network cards of this type are installed in the computer system unit additionally (as a separate expansion card) or as another external device.
First, let’s talk about PCI network cards. The abbreviation stands for (Peripheral Component Interconnect) – the interconnection of peripheral components or – the input-output bus for connecting peripheral devices to the motherboard of the computer. These cards are called so for the reason that they are installed in one of the PCI slots (slots). Here in these, in fact:
The PCI interface itself has a peak bandwidth for the 32-bit version, operating at a frequency of 33.33 MHz at 133 MB / s, the consumed voltage of the connector is 3.3 or 5V. Serves to install additional expansion cards (old video cards, modems, network adapters, TV tuners of various video capture and video conversion boards, etc.) into the computer.
So what network cards are installed there? But these are the most ordinary dollars for five or six:
There are adapters and another variety – Wi-Fi (for organizing wireless networks).
As you can see, the connection interface is one (PCI), but the principle of operation is different.
Now, due to the gradual “withering away” of this interface, network cards of the Pci Express 1X form factor are being issued.
PCI Express 1x Network Card PCI Express 1x Network Card
This applies to external network cards. There are also built-in (integrated into the motherboard) cards. You can determine the presence of an integrated network by looking at the back wall of the system unit.
Built-in network card
Here we can visually observe the output of the integrated network card. Next to the twisted pair connector, one or more information LEDs are installed, according to which you can orient about the connection and the overall activity of the network.
By the way, these LEDs can indirectly make an idea about the performance of the device. I’ll explain my thought: when the computer is turned on and the network cable (twisted pair) is connected to the card, the LED on it blinks, as they say, in time with the reception (transmission) of information packets of data by the adapter to the network.
If the network adapter is not working, the indicator behavior may be as follows:
Not one of the LEDs lights up at all
LED constantly “on” (without blinking)
The indicator flashes, but it is absolutely monotonous. The period and amplitude of this “blinking” are the same throughout the entire time.
So – note such moments. In detail – everything is ours! 🙂
If you go further and open the computer case, then inside (not far from the connector) you can find a chip soldered on the motherboard, which implements all the functions of a network adapter.
By marking we see that this is an RTL chip (from Realtek) under the number 8211BL.
Note: the integrated solutions, unfortunately, are not reliable. In our organization, for example, failures of integrated network cards happen regularly. I can’t say that often, but it’s stable. By the way, my network computer (bought half a year ago) literally the other day burned out a network card, which once again strengthened my opinion about the unreliability of integrated components. I had to put the external.
I want you to carefully look at the following photo:
Here we look inside the network card connector. Notice the difference? There are four pads in one connector (pictured right) and eight in the other (left). Moreover, both cards are designed for a network transfer rate of 100 megabits per second.
What is the catch here? And he, by any means, is present here 🙂 Let’s recall with you what the twisted pair cable looks like, see photo.
Correctly, it is called a UTP cable (Unshielded Twisted Pair – unshielded twisted pair cable). The fact that it is twisted (twisted) we perfectly see from the photo above. Its individual conductors are entwined with each other to improve the noise immunity of the entire cable as a whole.
The designation “unshielded” means that on top of the veins there is no additional protective screen (braid) made of foil or metal. Again – for better cable security. A “pair” because the conductors in the cable are twisted in pairs and by colors (white-orange – orange, white-green – green, white-brown – brown, white-blue – blue).
Now – the most important thing: to ensure data transmission over the network at a speed of 100 megabits per second, you do not need to use all four pairs (eight conductors-veins), just two pairs (four wires)!